SQL Injection exploits a vulnerability in the software of the applications.
See Also: What is Cross-Site Scripting (XSS) and How to Prevent It? The attacker adds new SQL statements to the relevant field on the standard application screen, using SQL language features. SQL Injection is an attack method used to attack applications that are driven by databases. Malicious people commonly use injection defects to compromise applications. PCI DSS Requirement 6.5.1 requires that your organization’s applications are not affected by injection flaws, especially SQL injection.
What Are The Defense Methods Against SQL Injection Attacks?